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The Formation of Giant Planetshttps://lup.lub.lu.se/search/publication/9ebcdc34-0848-42d9-a21c-a75bb1e9ddca
Lambrechts, Michiel2015Giant planets form embedded in a protoplanetary disc around a young star. Close to the midplane a large fraction of the available mass in solids is found in particles of cm to dm in size, which drift towards the star due to friction with the surrounding gas.
In paper I, II, III we describe a novel theory that explains how embryos, planetesimals larger than ~1000 km, grow efficiently by sweeping up the surrounding pebbles. The accretion radius of the embryo is large because gas drag aids the settling of passing pebbles to the core. In this way, the formation of large cores of 10 Earth masses is possible even in wide orbits (beyond the current Jupiter orbit), which previously could not be achieved when only considering the accretion of building blocks with sizes larger than km in size. Such high core masses are necessary for the attraction of massive gaseous envelopes, like the ones around the giant planets Jupiter and Saturn.
The above model relies on large planetesimal seeds to form and particles to settle to the midplane.
In paper IV, we study the previously unexplored sedimentation of particles in fluids with high dust-to-gas ratio and detect spontaneous clumping which could aid the sedimentation and formation of a midplane of pebbles in the outer disc.application/pdfhttp://lup.lub.lu.se/record/5154501urn:isbn:978-91-7623-269-9scopus:84934288234enginfo:eu-repo/semantics/closedAccessAstronomi, astrofysik och kosmologiPlanet formationSolar SystemExoplanetsGiant planetsHydrodynamicsThe Formation of Giant Planetsthesis/doccompinfo:eu-repo/semantics/doctoralThesistextThe PLATO 2.0 missionhttps://lup.lub.lu.se/search/publication/7c00bab0-37e5-44ae-8844-6956a07b4a25
Rauer, H.Catala, C.Aerts, C.Appourchaux, T.Benz, W.Brandeker, A.Christensen-Dalsgaard, J.Deleuil, M.Gizon, L.Goupil, M. -J.Guedel, M.Janot-Pacheco, E.Mas-Hesse, M.Pagano, I.Piotto, G.Pollacco, D.Santos, N. C.Smith, A.Suarez, J. -C.Szabo, R.Udry, S.Adibekyan, V.Alibert, Y.Almenara, J. -M.Maro-Seoane, P. A.Ammler-von Eiff, M.Asplund, M.Antonello, E.Barnes, S.Baudin, F.Belkacem, K.Bergemann, M.Bihain, G.Birch, A. C.Bonfils, X.Boisse, I.Bonomo, A. S.Borsa, F.Brandao, I. M.Brocato, E.Brun, S.Burleigh, M.Burston, R.Cabrera, J.Cassisi, S.Chaplin, W.Charpinet, S.Chiappini, C.Church, RossCsizmadia, Sz.Cunha, M.Damasso, M.Davies, Melvyn BDeeg, H. J.Diaz, R. F.Dreizler, S.Dreyer, C.Eggenberger, P.Ehrenreich, D.Eigmueller, P.Erikson, A.Farmer, R.Feltzing, Sofiade Oliveira Fialho, F.Figueira, P.Forveille, T.Fridlund, M.Garcia, R. A.Giommi, P.Giuffrida, G.Godolt, M.Gomes da Silva, J.Granzer, T.Grenfell, J. L.Grotsch-Noels, A.Guenther, E.Haswell, C. A.Hatzes, A. P.Hebrard, G.Hekker, S.Helled, R.Heng, K.Jenkins, J. M.Johansen, AndersKhodachenko, M. L.Kislyakova, K. G.Kley, W.Kolb, U.Krivova, N.Kupka, F.Lammer, H.Lanza, A. F.Lebreton, Y.Magrin, D.Marcos-Arenal, P.Marrese, P. M.Marques, J. P.Martins, J.Mathis, S.Mathur, S.Messina, S.Miglio, A.Montalban, J.Montalto, M.Monteiro, M. J. P. F. G.Moradi, H.Moravveji, E.Mordasini, C.Morel, T.Mortier, A.Nascimbeni, V.Nelson, R. P.Nielsen, M. B.Noack, L.Norton, A. J.Ofir, A.Oshagh, M.Ouazzani, R. -M.Papics, P.Parro, V. C.Petit, P.Plez, B.Poretti, E.Quirrenbach, A.Ragazzoni, R.Raimondo, G.Rainer, M.Reese, D. R.Redmer, R.Reffert, S.Rojas-Ayala, B.Roxburgh, I. W.Salmon, S.Santerne, A.Schneider, J.Schou, J.Schuh, S.Schunker, H.Silva-Valio, A.Silvotti, R.Skillen, I.Snellen, I.Sohl, F.Sousa, S. G.Sozzetti, A.Stello, D.Strassmeier, K. G.Svanda, M.Szabo, Gy. M.Tkachenko, A.Valencia, D.Van Grootel, V.Vauclair, S. D.Ventura, P.Wagner, F. W.Walton, N. A.Weingrill, J.Werner, S. C.Wheatley, P. J.Zwintz, K.2014PLATO 2.0 has recently been selected for ESA's M3 launch opportunity (2022/24). Providing accurate key planet parameters (radius, mass, density and age) in statistical numbers, it addresses fundamental questions such as: How do planetary systems form and evolve? Are there other systems with planets like ours, including potentially habitable planets? The PLATO 2.0 instrument consists of 34 small aperture telescopes (32 with 25 s readout cadence and 2 with 2.5 s cadence) providing a wide field-of-view (2232 deg(2)) and a large photometric magnitude range (4-16 mag). It focuses on bright (4-11 mag) stars in wide fields to detect and characterize planets down to Earth-size by photometric transits, whose masses can then be determined by ground-based radial-velocity follow-up measurements. Asteroseismology will be performed for these bright stars to obtain highly accurate stellar parameters, including masses and ages. The combination of bright targets and asteroseismology results in high accuracy for the bulk planet parameters: 2 %, 4-10 % and 10 % for planet radii, masses and ages, respectively. The planned baseline observing strategy includes two long pointings (2-3 years) to detect and bulk characterize planets reaching into the habitable zone (HZ) of solar-like stars and an additional step-and-stare phase to cover in total about 50 % of the sky. PLATO 2.0 will observe up to 1,000,000 stars and detect and characterize hundreds of small planets, and thousands of planets in the Neptune to gas giant regime out to the HZ. It will therefore provide the first large-scale catalogue of bulk characterized planets with accurate radii, masses, mean densities and ages. This catalogue will include terrestrial planets at intermediate orbital distances, where surface temperatures are moderate. Coverage of this parameter range with statistical numbers of bulk characterized planets is unique to PLATO 2.0. The PLATO 2.0 catalogue allows us to e. g.: - complete our knowledge of planet diversity for low-mass objects, - correlate the planet mean density-orbital distance distribution with predictions from planet formation theories,- constrain the influence of planet migration and scattering on the architecture of multiple systems, and - specify how planet and system parameters change with host star characteristics, such as type, metallicity and age. The catalogue will allow us to study planets and planetary systems at different evolutionary phases. It will further provide a census for small, low-mass planets. This will serve to identify objects which retained their primordial hydrogen atmosphere and in general the typical characteristics of planets in such a low-mass, low-density range. Planets detected by PLATO 2.0 will orbit bright stars and many of them will be targets for future atmosphere spectroscopy exploring their atmospheres. Furthermore, the mission has the potential to detect exomoons, planetary rings, binary and Trojan planets. The planetary science possible with PLATO 2.0 is complemented by its impact on stellar and galactic science via asteroseismology as well as light curves of all kinds of variable stars, together with observations of stellar clusters of different ages. This will allow us to improve stellar models and study stellar activity. A large number of well-known ages from red giant stars will probe the structure and evolution of our Galaxy. Asteroseismic ages of bright stars for different phases of stellar evolution allow calibrating stellar age-rotation relationships. Together with the results of ESA's Gaia mission, the results of PLATO 2.0 will provide a huge legacy to planetary, stellar and galactic science.http://lup.lub.lu.se/record/4979450http://dx.doi.org/10.1007/s10686-014-9383-4wos:000345385300010scopus:84943014904engExperimental Astronomy; 38(1-2), pp 249-330 (2014)ISSN: 0922-6435Astronomi, astrofysik och kosmologiExoplanetsAsteroseismologyTransit surveyStellar scienceExoplanetary scienceThe PLATO 2.0 missioncontributiontojournal/articleinfo:eu-repo/semantics/articletext